Up-to-date PSHA along the Gulf of Aqaba-Dead Sea transform fault

Abstract

The Gulf of Aqaba Dead Sea Transform fault (DSTF) is a plate boundary. Its southern section separates Sinai Peninsula, Egypt and Saudi Arabia. Also, it passes through several countries. A development plan with a huge budget is drawn to develop the Gulf of Aqaba region. This plan includes the construction of King Salman Bridge. Therefore, the assessment of the seismic hazard (SH) at this seismically active region is inevitable for the sustainability of these mega projects. This paper presents a probabilistic seismic hazard assessment (PSHA) study along the DSTF. An earthquake catalogue including the paleo-seismological studies, historical records and instrumental seismicity is compiled. It is processed by converting various magnitude types to the moment magnitude (Mw) using recently derived mathematical equations. Three de-clustering techniques have been used to de-cluster the catalogue. Then, a completeness test is performed. The obtained earthquake catalogue is implemented to plot two different smoothed seismicity maps (SSMs). These maps and two areal source models are utilized to represent the seismicity along the DSTF. Five ground-motion prediction equations (GMPEs) are used to predict the ground-motion, three out of them are for the seismic sources located at shallow active crust tectonic regime and two for the intermediate depth earthquakes generating at the subduction zone south of Cyprus. The previously mentioned SH inputs are implemented through the logic-tree framework. The produced maps illustrate that the PGA values in the DSTF region range from 0.02g to 0.4g and 0.06 to 0.48 for 475 and 2475 years return period (RP), respectively. Also, seismic hazard maps using the non-de-clustered catalogue are produced.